Really, the only 'quality' FMC out there is the OpticalRendu, quality voltage regulation, filtering, clocking. Runs warm, not hot so reliability should be good, hot is enemy of longevity, I'd send back any component that runs hot 24/7, won't last. I do recall conversation about running Uptone and other network devices from lower voltage lps, lets say device can run on anything from 7v-12v, run on 7v for cooler running, max reliability. But then I also recall some claiming these devices sound best when running max voltages. I've run network devices on a variety of voltages, can't say I've heard any noticeable difference in SQ.
So, first listening session with Finisar 1475 in OpticalModule, OpticalRendu, also AfterDark Ref 2m optical cable. First of all absolutely no glitches, drop outs, nothing out of ordinary. On to SQ, sorry if I sound like I'm blathering, but I can only say, WOW! Talk about revealing/resolving/transparency, this set far surpassed my expectations! The lowest level details are now resolved, and the higher level info in mix is more nuanced in that performers have become even more real, breath for singers, technique for all the other instrument, things like use of bow on violins, fingering on guitars, it all becomes more real. Sound stage has even greater precision, size, more organized and individualized performers, greater image dimensionality, each performer within a bubble of 3D air, so natural integration with rest of performers, in other words, no cookie cutter images which is something I've heard with some other network upgrades tried in past. Some think precisely drawn images is a good thing, and symptomatic of best quality clocking. I totally disagree, live performers don't have tightly drawn images, don't want my system reproducing hifi pyrotechnics, I'll take natural sound stage and images any day. Bottom line this level of resolution/transparency is both addicting and revelatory!
Now I come to another important aspect of performance I desire from my source, whether analog or digital, this being timing and/or flow. Analog does this well, digital has a harder time, jitter being the culprit. First few listening hours felt things a bit uptight, not terrible, but not what I had been experiencing with stock transceivers. Also things felt a little closed in, not quite as much spaciousness as before. Over the hours spaciousness was first to come back, by last couple hours greater sense of ease imparted. Presume this burn in issue, symptoms typical of lack of burn in. 24 hours, beginning of session, 30 by end. Final judgment awaits with more burn in, also still in final stages of Duelund Cast coupling capacitors burn in in 300B amps.
Bottom line on these upgrades. This is far more than incremental improvement, rather its meaningful, profound, one of the greatest improvements I've experienced from network upgrades, could turn out to be number one. I also have to take into account this result after having fully optimized every single link in streaming chain, already had extreme level of resolution/transparency, thus, this change magnified by what had come before. Now, on a possible downside, I could see this upgrade as possibly too revealing for systems with ANY prior defect. If one has some undesired coloration this will expose it without mercy. Keep in mind, I'm not fully burned in so I may detect more forgiving nature in time, but I expect this more forgiving nature will come from the flow/timing thing. I don't expect there's any flavor with this upgrade, no warmth added, just purely revealing, not unforgiving, not forgiving, just is.
@thieliste has more experience with various transceivers, perhaps he can offer advice for those who may suspect 1475 may be excessively revealing for their current setup, perhaps the 1318 is better fit. I can only say these modules are like having an entirely new streamer, seems much of OpticalRendu performance hinges on these transceivers!